Electrical igniting device for gas-engines



' {No Model.)

H. S. MAXIM.

ELECTRICAL IGNITING DEVICE FOR GAS ENGINES. N0. 296,341.

Patented Apr. 8,1884.

N. PCTERS. Phulu-Lilhagmphon Washmglmx B. c.

UNITED STATES PA'rnNr tries.

HIE-AM S. MAXIM, OF BROOKLYN, NEXV YORK.

ELECTRICAL lG-NITING DEViGE FOR GAS-ENGINES.

SPECIFICATION forming part Of Letters Patent No. 296,341, dated April 8, 188%.

Application filed January 12, 1884. (No model.) Patented in France October 6, 1853.

T0 whom zit may concern:

Be it known'that I, HIRAM S. MAXIM, a

citizen of the United States, and a resident of Brooklyn, in the county of Kings and State of New Yogk, have invented certain new and useful Improvements in Electrical Igniting Devices for Gas-Engines, of which the following is a specification, reference being had to the drawings accompanying and forming a part of the same.

My invention relates to apparatus for effecting the ignition or explosion of gaseous mixtures in gas engines or motors by means of an electric spark.

The objects of the invention are to simplify the construction and to render more certain the action of the devices for accomplishing this, and to avoid the employment of the galvanic or similar generators which have been required hitherto. I

The main features of my invention are the following: Upon the legs of a strong permanent magnet, or the cores of an electro-mag net, I place bobbins of insulated wire containing a number of layers orconvolutions. In face of the poles of this magnet I arrange an armature, pivoted in such position as to be encountered hy a moving part of the engine at the proper moment, and detached from the poles to which it is held by magnetic attraction. W'ithin any part of the explosion-chamber of the engine are placed two contact strips, pins, or the like, one of which is connected with the pivoted armature in such manner as to be moved by the retraction of the same out of contact with the other. The ends of the wire composing the bobbins are connected to the strips or contact-points, and the latter are properly insulated. ,These devices are so arranged that the armature will be encountered by the part of the engine designed for that purpose at the moment when it is desired to produce the explosion of the gaseous mixture under the piston of the engine. The move ment of the armature away from the magnet induces a current in the coils surrounding the latter, which current being interrupted by the separation of the contact-points within the explosion-chamber produces a spark which ignites the charge of gas.

This invention, the general nature of which I have how described, is applicable to many varieties of gas motors or engines. In more particularly describing the construction and operation of the same, however, I will refer to the accompanying drawings, which illustrate a special form of engine invented by me, and to which my improved exploder is applied.

Figure l is a central vertical section of the engine complete. Fig. 2 is a modified form of magnet tobe used with the exploding devices, and Fig. 3 is a sectional view of a detail.

A and B are two pistons, the piston B having'an area of rather more than twice that of piston A. These two pistons are cast in-one piece, and are connected to a piston-rod which operates a crank-shaft,0 O. Thepistons work in a vertical cylinder, which is cast in one piece, and has a portion, B, of sufficient diameter to receive the piston B, and a smaller portion, A, in which works the piston A.

Below the piston A is a space, T, known as the explosion-chamber in engines of this character. This explosionchamber and the the usual water-jackets, S, through which a circulation of water is maintained during the operation of the engine.

On the crank-shaft O is placed a pulleywheel and ally-wheel, In the latteris a frame, K K, supporting a hinged weight, H, which is held to the hub of the fly-wheel by means of a stout spiral spring, p.

Through a projection from the hub of the fly-wheel passes a spindle, J, on which is a loose sleeve formed with a rim, I, the whole constituting a shitting-roller. An arm, 1", extending from the weight H, engages with this roller. The tension of the spring 1) is adjusted by means of a set-screw, q. These parts constitute the governing mechanism, and their functions will be explained more fully hereinafter. Entering the space T below the piston A is a passage, D, connected to a chamber, a, into which extends the perforated end of agas-pipe, E. A valve, F, kept closed by a spring, is placed at the upper end of chamber u. Communication between the passage D and chamber a is closed by a valve, 0, the stem of which passes through the wall of chamher a, and is surrounded by a spiral spring, 6.

portion of the cylinder A are surrounded by 7 G is a bell-crank lever, pivoted to a support on the base of the engine. One end of this lever bears upon the end of the stem of valve 0. The other end of lever G is connected to a rod, M, the end of which is turned backupon itself. A wheel or pin, L, is placed on the cylinder or other convenient part of the engine, and serves to keep the rod M in place, while permitting it to move freely up and down. In the normal operation of the engine, the rounded or beveled end of rod M lies in the path of movement of the roller I.

In the bottom of the cylinder T is a spring valve, 1?, opening inward for the admission of air, and in the passage D is a smaller valve, 6, for a similar purpose.

Between the two portions A and B is an I enlargement containing an annular space, U.

Above this space is a ring, K, of'the same diameteras the portion A of the cylinder. Above this ring is a second annular space, V, from which leads a pipe containing an exhaust valve, (not shown in the'drawings,) provided with a spiral spring, the tension of which may be adjusted in any ordinary manner.

The operation of an engine constructed in the manner described is as follows: The proper connections are made with the gas-main and a circulation of water started in the jacket S. The pistons A B are then set in motion by revolving the crank-shaft 0. As the piston A ascends, it draws in air through the valves P and e. The springs which close the valves, however, )revent a full atmosphere entering. A partial vacuum is thus produced inthe cylinder A. The piston B in its upward movement also produces a partial vacuum in the chamber or annular space V. \Vhen it has reached a point where the piston A is wholly withdrawn from its cylinder, there is a full connection established through the annular space U into the chamber V. The air passes freely, therefore, from one chamber to the other until the same degree of vacuity exists in the chamber T as exists in the space or chamber V. As the crank-shaft is rotated, the piston A descends and closes off the communication be tween the cylinder A and the space U. At this moment the roller I is brought in contact with the end of rod M, which, operating through the bell-crank lever G and the ad justing-screw N, presses the valve 0 open, thus admitting sufficient gas or gas and air through 0 to bring the pressure in the exploding-chamber T to one atmosphere. The descent of the piston A compresses the gases in the cylinder A until a pressure of about forty pounds is attained. At this moment the exploding device is brought into operation and the gaseous mixture ignited. By the force of the explosion the piston is driven upward with great force. As it passes in its upward stroke beyond the space U, the gas below it will be instantly sucked out into the chamber V, and as there is not gas sufficient to fill this chamber air will be drawn in through 1? and 6. Then, when the piston descends again, the space beneath it will be partly filled with pure air, until .the piston has reached a point where the valve 0 is opened as before, when sufficient gas will enter at O to produce one atmosphere of explosive m1xture at T. It is desirable that a small proportion of air should enter the explosion-chamber along with the charge of gas. For th1s purpose the valve F is employed.

The operation of the governor is similar to those described by me in other applications, the principle of operation being to regulate the number of charges rather than the quality of each individual charge. It Will thus be understood that any increase above the normal speed of .the engine will cause the weight H to recede from the hub of the flywheel by centrifugal action, in this way shifting the sleeve or roll I out of line with the plate M, so that the latter is not depressed, and the valve 0 in consequence not openeduntilthe normal speed has been again reached, when the roller IWill .be brought back into posit-ion to operate the rod M.

- Having now described the general character and operation of the engine, I will describe the igniting devices which constitute the invention.

/ R is a horseshoe-magnet secured in a con- ;venient manner to the frame or cylinder of the g engine. Upon the ends of this magnet are 5 coils of insulated wire, R. Below the poles of the magnet is a pivoted lever, r, carrymg an armature, s. Passing through the walls of the passage D are two'metal pins, ab. The ,lower pin, b, passes through a screw-plug, a, and bushing 0, both of insulating materlal, and is fitted in such way as to be capable of I adjustment. The pin a passes through a screwplug, a, of insulating material,which has a per- ,foration of sufficient diameter to permit the said pin to move freely through it. The pin Ea passes through a perforation in the end of the armature-lever, and has a head, d. These iparts are so adjusted that when the armature {s is in contact with the poles of the magnet, or is drawn up to its highest position by the same, the pins'a I) will be in contact, but will be separated by the retraction of the armature by {the raising of the pin a. The ends of the coils R are connected to the pins one directly to the pin b, the other by means of a spring, f, attached to the lever r and bearing on the head of pin a.

WV is a rod held by one or more guides, or, secured to the frame or cylinders of the engine. The lower end of this rod passes through a perforation in thelong arm of the lever 7", and is provided with an adjustable nut, o.

W is a bar joined to the upper end of rod W, and carried around the shaft 0, on which is a cam, f, that raises the bar during a portion of the revolution of the engine, and permits it to suddenly drop at the moment when the charge is to be exploded in the cylinder T. To insure the proper action of the bar, a

296,341 a r a spring, I), secured to the cylinder or frame of the engine, presses the bar W or rod XV downward.

The operation of these parts will be readily understood. Normally the pins a I) remain in contact. By the movement of the engine the charge of air and gas is admitted to the space T and the passage D. When the piston A has reached the desired point in its descent, re the bar XV and rod WV are dropped by the cam f and the spring 6, the armature suddenly retract-ed from the poles of the magnet, and a current induced in the coils R, which flows through the pins a b. Simultaneously with I5 thpgegelgpment of thiscurrent. the pin a is raisedfrom pin Z). This gives rise to a spark betwee n the twothat eipl'odes' thechargei f The construction described is given merely as an example of many similar forms that may be used.

I do not confine myself to the use of any special form of contact pins or strips, nor to the specified means of effecting their separation. It is obvious. too, that the character and arrangement of the magnet, the coils, and

armature, which together constitute a magneto-electric generator, may be greatly varied. For example, an electro-magnet maybe used in lieu of a permanent one, and any 0 meangpmployed ofefiecting the separation or withdrawal fromits poles of the armature; but,

Having described the main and essential features of the invention and the manner of applying the same to an engine, what I claim 1. The combination, with a gas-engine, of a magnet and movable armature-coils upon the magnet, a circuit carried through the chamher or space for containing the explosive o charge, and mechanism connected with a moving part of the engine and operated thereby for causing a sudden movement of the armature and breaking the circuit within the explosion-chamber, all substantially as set forth.

2. The combination, with a gas-engine, of 5 separable contact-pins arranged within the chamber or space for containing the charge, a magnet with coils in circuit with said pins, a movable armature connected with one of the pins, and mechanism connected with a mov- 5o ing part of the engine and operated thereby for effecting the retraction of the armature from the magnet and the separation of the pins within the explosion-chamber, all substantially as set forth.

3. The combination, with a gas-engine, of separable contact-pins arranged within the chamber or space for containing the charge, a magnet with coils in circuit with said pins, a movable armature connected with one of the pins, and a rod operated by a cam on the shaft of the engine for effecting the withdrawal of the armature from the magnet and the separation of the pins within the explosion-chamber, all substantially as set forth.

4. The combination, with a gas-engine, of separable contact-pins arranged within the chamber or spacefor containing the charge, a magnet with coils in circuit with said pins, a movable armature connected with one of the pins, and aspring-actuated rod operated by a cam on the shaft of the engine for effecting the withdrawal of the armature from the magnet and the separation of the pins within the explosion-chamber, all substantially as set forth.

In testimony whereof lhave hereunto set my hand this 17th day of December, 1883.

' HIRAM S.- MAXIM.

\Vitnesses:

H. H. NEWMAN, F. J. Wnrriuonn, Consulate General, U. S. A.., London. 

